Phone numbers given to Facebook for security purposes can be used to search for profiles

“Facebook shouldn’t be using people’s personal security information for anything other than security. But in fact, they’ve used it in a way that undermines users’ security and exploited it for advertising,” Silkie Carlo, director of civil liberties group Big Brother Watch, told i.

“This poses a serious risk to dissidents and human rights campaigners who use the platform, but more widely damages users’ trust in vital security measures. Facebook has time and time again demonstrated a total failure to take user’s privacy and safety seriously. This is the latest in Facebook’s long string of inexcusable failures.”